1. Field of the Invention
This invention relates to a lumbar support located inside the back of a chair of the kind which rocks back and forth, such as that commonly found in an office or home so that a user can be seated close to a work surface (e.g., a desk or a table). The lumbar support is adapted to progressively change its shape from an arced, convex configuration to a substantially flat configuration in response to a pressure applied to the chair back so as to provide support and maintain a proper posture of the user's back when the chair back stands upright and the user's back is erect and close to the work surface and when the chair back rocks backwards and the user reclines away from the work surface.
2. Background Art
A wide variety of chairs have been used in an office or at home to enable a user to be seated adjacent a work surface. In this case, the user can access a computer, a book, a writing pad, etc. which lays upon the work surface so that the user can work while seated. Some chairs are adapted to rock back and forth in response to the user shifting his weight backwards and forwards. With the chair rocked forwards, the user's back is located close to the work surface during which work can be accomplished. When the chair rocks backwards, the user's back is correspondingly reclined and tilted away from the work surface to enable the user to relax.
A common problem with such conventional office and home chairs occurs when the chair rocks forward and the user tries to hold his back erect and close to the work surface. In particular, even when the back of the chair stands upright, the back of the user is usually spaced forwardly from the chair back. Therefore, the chair back offers little or no support for the user's lower back throughout those times when the user is working. Consequently, the user's back posture may suffer and, especially during long periods of work, the user may experience lower back pain and discomfort. What is even more, when the chair rocks back, the back of the chair typically retains its initial shape and is therefore unable to adjust for an increased compressive force generated by the user leaning against the chair back.
What would be desirable is a chair which overcomes these problems to enable the user's back to be adequately supported by the chair back so that a proper posture is maintained and comfort is enhanced when the chair rocks forward and back. Reference may be made to my pending patent application Ser. No. 14/051,251 filed Oct. 10, 2013 for an example of a dynamic lumbar support located in the back of a chair to improve posture and comfort.